The present invention relates generally to closure devices and, more particularly, to a slider having a shape which causes the user to grip the slider in a predetermined manner. The invention is particularly well suited for flexible storage containers, including plastic bags.
The use of closure devices for fastening storage containers, including plastic bags, is generally known. Furthermore, the manufacture of closure devices made of plastic materials is generally known to those skilled in the art, as demonstrated by the numerous patents in this area.
A particularly well known use for closure devices is in connection with flexible storage containers, such as plastic bags. In some instances, the closure device and the associated container are formed from thermoplastic materials, and the closure device and the sidewalls of the container are integrally formed by extrusion as a single piece. Alternatively, the closure device and sidewalls of the container may be formed as separate pieces and then connected by heat sealing or any other suitable connecting process. In either event, such closure devices are particularly useful in providing a closure means for retaining matter within the bag.
Conventional closure devices typically utilize mating fastening strips or closure elements, which are used to selectively seal the bag. A slider may be provided for use in opening and closing the fastening strips. Some of these sliders may include a separator which extends at least partially between the fastening strips. When the slider is moved in the appropriate direction, the separator divides the fastening strips and opens the bag.
One of the difficulties involved with using a slider is the manner in which the user grips the slider. Generally, the slider is gripped in the center. This situation requires that the slider be pulled which requires more force than if the slider were pushed. Additionally, if the slider is gripped towards the bottom, the shoulders of the slider may tear into the sidewalls of the plastic container or the fastening strips.
The present invention provides a closure device with a slider having a specific shape that results in the slider being gripped in a certain fashion. The closure device comprises first and second interlocking fastening strips arranged to be interlocked over a predetermined length. The slider is slidably disposed on the interlocking fastening strips for facilitating the occlusion and deocclusion of the fastening strips when moved towards first and second ends of the fastening strips. The external surface of the slider is designed to alter the way in which the slider will be grasped by the user. By providing outwardly protruding portions on the side portions of the slider, the slider will be grasped near the front or back of the slider. Thus, the slider will be easier to move along the fastening strips because the gripping forces by the user will be reduced. In another embodiment, by providing a gripping surface near the top portion of the slider, the slider will be grasped near the top portion of the slider. Thus, the slider will be easier to move and the slider reduces the tearing that may result when too much pressure is applied to the bottom portion of the slider during movement of the slider.